package  cn.qiku.rf.effects.easing
{

public class Sine
{


	public static function easeIn(t:Number, b:Number,
								  c:Number, d:Number):Number
	{
		return -c * Math.cos(t / d * (Math.PI / 2)) + c + b;
	}

	public static function easeOut(t:Number, b:Number,
								   c:Number, d:Number):Number
	{
		return c * Math.sin(t / d * (Math.PI / 2)) + b;
	}

	public static function easeInOut(t:Number, b:Number,
									 c:Number, d:Number):Number
	{
		return -c / 2 * (Math.cos(Math.PI * t / d) - 1) + b;
	}
}

}
